Blast furnace tuyere



Feb. 15, 1966 J. c. TROY BLAST FURNACE TUYERE Original Filed Dec. 27, 1962 INVENTOR JOSEPH C. TROY his ATTORNEY United States Patent ()fiice 3,234,919 Patented Feb. 15, 1966 3,234,919 BLAST FURNACE TUYERE Joseph C. Troy, Pittsburgh, Pa., assignor to Jones &

Laughlin Steel Corporation, Pittsburgh, Pa., 21 corporation of Pennsylvania Continuation of application Ser. No. 247,650, Dec. 27, 1962. This application Dec. 30, 1964, Ser. No. 425,671

Claims. (Cl. 122-66) This invention relates to tuyeres and is particularly concerned with tuyeres used in blast furnaces. This application is a continuation of my application Serial No. 247,650, filed December 27, 1962, now abandoned.

Blast furnaces, particularly iron blast furnaces, are supplied with air through a multiplicity of supply pipes which extend into the blast furnace and terminate as nozzles or tuyeres which project through part of their length into the furnace interior. These tuyeres must, therefore, be capable of withstanding the temperatures reached inside the furnace and are quite commonly made in the form of castings of copper or copper alloy of high thermal conductivity. In addition, the tuyeres are commonly Water-cooled. The hottest portion of the tuyere is its inside end or nose, and it is here that tuyere failure usually occurs. In the past attempts have been made toimprove the cooling of the tuyere nose by bringing the cooling water directly to the nose and allowing it to flow back to the discharge through the tuyere walls, the theory being that the hottest portion of the tuyere should be in contact with the coolest water. I have found that contrary to what might be expected, improved cooling is obtained in a tuyere structure in which the cooling water is introduced at the base of the tuyere and is caused to circulate spirally with increasing velocity toward the nose of the tuyere, and back again to a discharge outlet at the base.

It is, therefore, an object of my invention to provide a water-cooled tuyere in which the cooling water transfers heat rapidly from the nose portion of the tuyere. It is another object to provide a water-cooled tuyere of simple construction in which the cooling water travels spirally in the tuyere wall. It is still another object to provide a water-cooled tuyere in which the cooling water travels spirally at a greater speed in the tuyere nose than in other portions of the tuyere. Other objects of my invention will appear in the course of the following description thereof.

An embodiment of my invention presently preferred by me is illustrated in the attached figures to which reference is now made.

FIGURE 1 is an elevation in section of a tuyere of my invention.

FIGURE 2 is an end elevation of the base end of the tuyere of FIGURE 1.

FIGURE 3 is a cross section of a portion of the tuyere shown in FIGURE 2 taken on the plane 3-3.

My tuyere comprises a body portion 1 which is of frusto-conical shape with its axis inclined to its base 2. A cylindrical bore 3 extends throughout the tuyere more or less coaxial with its inclined axis. Nose portion 4 is at the opposite end from base 2. Body portion 1 is formed with an elongated internal cavity 6 extending from the region of the tuyere base 2 toward the tuyere nose 4. Cavity 6 is separated from bore 3 by inner wall 16, and is enclosed by outer wall 5. Tuyere body 1 is thinner in region 7 of nose 4 than it is at other points around the circumference of nose 4. Because of this, the region 8 of cavity 6 adjoining region 7 is narrower than other portions of cavity 6. Within cavity 6 is positioned a frustoconical shell 9 which is attached to base portion 2, but stops short of the end of cavity 6 adjacent nose 4 of my tuyere. Shell 9, therefore, divides cavity 6 into an inner approximately cylindrical annular passageway 10, and an outer frust-o-conical annular passageway 11 which communicte circumferentially at their ends adjacent nose 4. In the region 8 both passageways 10 and 11 are narrower than they are near base 2. A port 12 is provided in base 2 opening into inner passageway 10 and a port 13 is also provided in base 2 opening into outer passageway 11. These ports '12 and 13 are spaced from each other approximately around the circumference of base 2. Base 2 is also provided with a second port 14 opening into inner passageway 10 diametrically opposite port '12, and a second port 15 opening into outer passageway 1-1 diametrically opposite port 13. Ports 14 and 15 are provided for clean out purposes and are normally plugged.

From inner wall 16, a baflie 17 extends into passageway -10 parallel to base 2 and spaced from port 12. Baffle 17 at its other end is attached to shell 9. Extending upwardly from base 2 into passageway 10 at the side of port 12 is a projection 18 which fills the space between inner wall 16 and shell 9 and closes off bafiie 17 at one end. Spaced from port 13 a baffle 19 extends from the outer Wall 5 of my tuyere in the same way as baffle 17 previously described, and a projection 20 exends into passageway 11 from base .2 closing off baflle 19 on one side of port 13. The open ends of baffles 17 and 19 face each other.

In the operation of my apparatus I introduce water into my tuyere through port 13. The water issues from port 13 into outer passageway .11 in a circumferential direction because of the presence of baffle 19. The water flows spirally through passageway 11 toward the nose 4 of my tuyere. The stream of water flows from passageway 1.1 to passageway 10 at their juncture and back spirally through passageway 10 to outlet '12 in base 2. As the length of the spiral path of the water in outer passageway 11 decreases toward the tuyere nose 4, the water accelerates in its travel therethrough because of the principle of the conservation of linear momentum, and reaches its maximum velocity in that passageway at its end adjacent nose 4. It further accelerates as it turns the corner into the communicating end of inner passageway 10, because that passageway is of shorter radius than outer passageway 11. In its return flow throng-11 inner passageway 11 the velocity of the water is greater than its velocity in outer passageway 10, and is approximately constant because inner passageway 10 is approximately cylindrical. Outer passageway 11 also narrows somewhat as it approaches region 8, and this narrowing also accelerates the water stream.

In my tuyere as above described the increase in the velocity of the cooling water as its approaches the nose portion of my tuyere increases its capacity to carry heat away from the tuyere. This increase in velocity is caused to take place at the region at maximum temperature.

Blast furnace tuyeres present a difiicult cooling problem which I have solved by my invention described herein. That invention is also applicable to nozzles of other de scriptions which require to be cooled by water or like cooling media, and I use the term tuyere herein to include such nozzles.

I claim:

1. A blast furnace tuyere having a base, a nose, and a hollow, approximately frusto-conical, body comprising an annular channel therein adjacent to the base thereof and extending toward the nose thereof, an annular wall in that channel extending from the base of the tuyere and stopping short of the nose end of the annular channel so as to divide the channel into an outer frustoconical passageway and an inner passageway which communicate at the nose end of the channel, a first cooling fluid port in the base of the tuyere communicating with the 'outer passageway, a second cooling fluid port in the base of the tuyere communicating with the. inner passageway, and first baffle means within the outer passageway and extendingaround a minor portion ofthe circumference thereof spaced from the first port sufiiciently to cause cooling fluid entering that passageway from that port to flow initially in a circumferential direction adjacent the base of the tuyere and then spirally through that passageway.

2. A blast furnace tuyere as in claim 1 including second bafile means within the inner passageway and extending around a minor portion thereof spaced from the second port sufliciently to cause cooling fluid entering that passageway from that port to flow initially in a circumferential direction adjacent to the base of the tuyere, that direction being opposite to the direction of cooling fluid flow from the first port.

3. A blast furnace tuyere as in claim 1' in which the outer passageway con-verges from the base of the tuyere toward the nose thereof.

4. A blast furnace tuyere as in claim 1 in which the annular channel converges from the base of the tuyere toward the nose of the tuyere throughout at least a portion of its circumference so as to decrease progressively the length of the spiral path of the cooling fluid through the outer passageway as it approaches the nose of the tuyere and to maintain substantially constant the length of the spiral path of the cooling fluid through the inner passageway.

5. A blast furnace tuyere as in claim 1-in which the first bafile means closes olf the outer passageway opposite the firstport except on one side thereof.

References flited by the Examiner UNITED STATES PATENTS 2,891,783 6/1959 Eberha-rdt 1226.6 X

FOREIGN PATENTS 615,076 2/1926 France.

451,232 10/ 1927 Germany. 719,138 3/ 1942 Germany.

FREDERICK L. MATTESON, 1a., Primary Examiner.

KENNETH W. SPRAGUE, Examiner. 

1. A BLAST FURNACE TUYERE HAVING A BASE, A NOSE, AND A HOLLOW, APPROXIMATELY FRUSTO-CONICAL, BODY COMPRISING AN ANNULAR CHANNEL THEREIN ADJACENT TO THE BASE THEREOF AND EXTENDING TOWARD THE NOSE THEREOF, AN ANNULAR WALL IN THAT CHANNEL EXTENDING FROM THE BASE OF THE TUYERE AND STOPPING SHORT OF THE NOSE END OF THE ANNULAR CHANNEL SO AS TO DIVIDE THE CHANNEL INTO AN OUTER FRUSTOCONICAL PASSAGEWAY AND AN INNER PASSAGEWAY WHICH COMMUNICATE AT THE NOSE END OF THE CHANNEL, A FIRST COOLING FLUID PORT IN THE BASE OF THE TUYERE COMMUNICATING WITH THE OUTER PASSAGWAY, A SECOND COOLING FLUID PORT IN THE BASE OF THE TUYERE COMMUNIATING WITH THE INNER PASSAGEWAY, AND FIRST BAFFLE MEANS WITHIN THE OUTER PASSAGEWAY AND EXTENDING AROUND A MINOR PORTION OF THE CIRCUMFERENCE THEREOF SPACED FROM THE FIRST PORT SUFFICIENTLY TO CAUSE COOLING FLUID ENTERING THAT PASSAGEWAY FROM THAT PORT TO FLOW INITIALLY IN A CIRCUMFERENTIAL DIRECTION ADJACENT THE BASE OF THE TUYERE AND THEN SPIRALLY THROUGH THAT PASSAGEWAY. 